The invention relates to a porous silica having an average pore diameter in the range of from 20 to 450 Å, a median (D50) pore diameter in the range of from 20 to 450 Å, a pore volume in the range of from 0.15 to 1.2 cm 3 g -1 , a surface area in the range of from 100 to 600 m 2 g -1 , and a span of 0.80 or less.
The invention also relates to a method of producing a porous silica, in which an aqueous phase comprising nanoparticulate silica and an organic phase are mixed together to form a water-in-oil dispersion or emulsion, in which the organic phase comprises an organic solvent that is insoluble or partially soluble in water, and optionally also a non-polar organic compound that is insoluble in water and at least partially soluble in the organic solvent, wherein a gelling agent is present in the aqueous phase such that the nanoparticulate silica gels to form a porous silica.